ABSTRACT
Enzymes are a special class of proteins that catalyze chemical reactions. In a cell, virtually all chemical reactions do not occur spontaneously because they could otherwise not be controlled by the cell. us, in most cases, cells employ enzymes for controlling chemical reactions. ere are two reasons for chemical reactions not to occur spontaneously in a cell: either they are energetically not favorable (i.e., the reaction requires energy) or a large activation energy barrier has to be overcome because it slows down the kinetics. In both cases, enzymes can help to catalyze these reactions.
